SHIWALIK RANGE.
The Sivalik Hills is a mountain range of the outer Himalayas also known as Manak Parbat in ancient times.
AREA-
This range is about 2,400 km (1,500 mi) long enclosing an area that starts almost from the Indus and ends close to the Brahmaputra, with a gap of about 90 kilometres (56 mi) between the Teesta and Raidak rivers in Assam. The width of the Sivalik Hills varies from 10 to 50 km (6.2 to 31.1 mi), their average elevation is 1,500 to 2,000 m (4,900 to 6,600 ft).
FORMATION-
The Shivalik Group is more recent and was formed in the period 15 million years to about 800,000 years ago. Rocks were formed out of the eroded rock material that was deposited into the lake like basin created by the Indian plate striking against the Tibetan plateau. There were differences in the type of material deposited over the geological ages leading to the Shivalik Group rocks being divided into 3 sub-groups:
a) The Lower Shivalik Group - The sedimentary rocks in this formation are characterized by the grey sandstone, siltstone and red mudstone. The sandstone is hard and resistant to erosion.
b) The Middle Shivalik Group- It includes sandstone of coarser material and grey-black mudstone and medium grained bright grey sandstone.
c) The Upper Shivalik Group - The group consists of pebbles, cobbles and boulders.
The Sivalik Hills is a mountain range of the outer Himalayas also known as Manak Parbat in ancient times.
AREA-
This range is about 2,400 km (1,500 mi) long enclosing an area that starts almost from the Indus and ends close to the Brahmaputra, with a gap of about 90 kilometres (56 mi) between the Teesta and Raidak rivers in Assam. The width of the Sivalik Hills varies from 10 to 50 km (6.2 to 31.1 mi), their average elevation is 1,500 to 2,000 m (4,900 to 6,600 ft).
FORMATION-
The Shivalik Group is more recent and was formed in the period 15 million years to about 800,000 years ago. Rocks were formed out of the eroded rock material that was deposited into the lake like basin created by the Indian plate striking against the Tibetan plateau. There were differences in the type of material deposited over the geological ages leading to the Shivalik Group rocks being divided into 3 sub-groups:
a) The Lower Shivalik Group - The sedimentary rocks in this formation are characterized by the grey sandstone, siltstone and red mudstone. The sandstone is hard and resistant to erosion.
b) The Middle Shivalik Group- It includes sandstone of coarser material and grey-black mudstone and medium grained bright grey sandstone.
c) The Upper Shivalik Group - The group consists of pebbles, cobbles and boulders.
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BY SONAL.